JPS62133424A - Projection type display device - Google Patents

Abstract

PURPOSE:To obtain a small-sized, light-weighted and clear screen free from color blurring up to its peripheral part by constituting the titled display device of liquid crystal lens and a dichroic mirror, synthesizing display images based upon three liquid crystal panels in the device through the dichroic mirror and projecting the synthesized image by a projection lens. CONSTITUTION:Visual light irradiated from an illuminating optical system is separated into three primary colors consisting of red, green and blue by the dichroic mirror. Three display panels 31-33 are arranged so that optical distances from a projection lens 13 are equal and respective display videos based upon the dichroic mirror are synthesized by the projection lens 13 and projected as an enlarged image. A blue display image 44, a red display image 45 and a green display image 46 are obtained by controlling respective display panels 31-33, the blue display image 44 is reflected by a blue reflecting mirror 28 and transmitted through a red reflecting mirror 29 and a blue reflecting mirror 30. The red display image 45 is reflected by the red reflecting mirror 29 and transmitted through the green reflecting mirror 30 and the green display image 46 is reflected by a green reflecting mirror 30 to obtain a synthesized display image 47 of the blue, red and green display images.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a dichroic mirror that separates and combines light, and a display, in a projection type display device, which is viewed as a means of obtaining display of the three primary colors necessary for full-color display. By using a liquid crystal panel that integrates thin film transistors in light pulp, it is small, lightweight, and has a large capacity with no color shift.
ty> Full color display has been realized.

[Conventional technology]

The configuration of a conventional projection display device is to use three cathode ray tubes for the three primary colors, each of which is provided with a projection lens, and to project images onto a screen.

Furthermore, even if a dichroic mirror was used for three-color synthesis, such as in JP-A-59-251987, a cathode ray tube was used for display.

[Problems and Objects to be Solved by the Invention] However, in the above-mentioned prior art, positioning on the screen is required each time the distance to the screen changes. Also, like the latter in the prior art mentioned above, which has the problem of large color shift around the screen,
A dichroic mirror may be used, but since it uses a cathode ray tube, it is difficult to make it small and lightweight, and a small cathode ray tube has the problem of poor display dispersion.

Therefore, the present invention aims to solve these problems.
The purpose is to provide a projection type display device that is small and light, has a large display capacity, and can display in full color.

[Means to solve the problem]

The projection display device of the present invention includes three dichroic mirrors that separate visible light emitted from a light source into red, green, and blue, which are the three primary colors in additive color mixture, and three dichroic mirrors that combine the three primary colors. It is characterized by being composed of three liquid crystal panels that integrate WIrIk transistors that perform display corresponding to each of the three primary colors.

[Effect]

According to the above configuration of the present invention, gradation display is possible using the liquid crystal panel integrated with thin film transistors, so full color display can be realized by using three panels. Further, since pixels can be configured depending on the purpose of use even on a liquid crystal panel of the same size, large-capacity display is possible.

The dichroic mirror combines the display of each of the three primary colors, so it is possible to obtain a clear image with no color shift even at the periphery of the screen.The dichroic mirror and liquid crystal panel are plate-shaped, making it possible to reduce the size and weight. can.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an external view of the projection display device, in which 10 is a cabinet and 11 is a handle used when moving the device. 1
Reference numeral 2 denotes an operation section where video control knobs, input terminals, etc. are arranged. 13 is a projection lens.

Figure 2 is a top view showing the internal configuration of the projection display device;
The figure is a side view showing the internal configuration.

In the figure, visible light emitted from a light source 20 composed of a halogen bulb or metal halide bulb and a reflector is transmitted through a lens 21. The light is collected by an optical system including a heat ray cut filter 22, a reflecting mirror 25, and a lens 24 to obtain visible light as approximately parallel light. Heat generated by the light source 20 is forcibly discharged by a heat dissipation fan 54.

Visible light emitted from the illumination optical system is separated into three primary colors of red, green, and blue by a dichroic mirror. In the embodiment, the blue light is separated by the blue reflection mirror 25 and illuminates the blue display panel 51 via the blue reflection mirror 28 . Red light is separated by the red reflecting mirror 26 and illuminates the red display panel 52. The remaining green light illuminates the green display panel 35. The image displayed on the green display panel 33 is the linear reflection mirror 27 and the green reflection mirror! It reaches the projection lens 13 via the IO, and the displayed image of the red display spring/l 152 reaches the projection lens 15 via the red reflective mirror 29. The displayed image on the blue display panel 31 passes through the red reflecting mirror 29 and the green reflecting mirror 30 and reaches the projection lens 13.

The three display panels are arranged so that the optical distances between the projection lenses 13 and 13 are the same, and the respective display images are combined by the projection lens 15 using a dichroic mirror and enlarged and projected.

Reference numeral 35 represents a leg for adjusting the projection angle, and reference numeral S6 represents a circuit section in which a control circuit and a power supply circuit are arranged.

FIG. 4 is a diagram showing the principle of spectroscopy and synthesis using a dichroic mirror.

In the figure, a blue component of visible light 40 is reflected by a blue reflection mirror 25 to obtain blue light 41. The light transmitted through the blue reflecting mirror 25 is converted into red light 42 by the red reflecting mirror 26,
The light transmitted through the red reflecting mirror 26 is converted into green light 45 by the green reflecting mirror 27. The blue light 41, red light 42, and green light 43 are respectively transmitted through the blue display panel (Sl) and red display panel (
32)-Illuminate the green display panel (35).

Each display panel displays an image corresponding to each color, and the display is performed by controlling the rate at which incident light is transmitted.

By controlling each display panel, a blue display image 44, a red display image 45, and a total display image 46 are obtained, and the blue display image 44 is reflected by the blue reflection mirror 28 and transmitted through the red reflection mirror 29 and the green reflection mirror 30. do.

The red display image 45 is reflected by the red reflection mirror 29 and transmitted through the green reflection mirror 30, and the line display image 46 is reflected by the green reflection mirror 30, resulting in a composite display of the blue display image, red display image, and line display image. Obtaining Image 47 In the embodiment, it is necessary to make the optical distances from the projection lens 13 to each display panel the same, so the blue display panel (31) has a green display at the position of the blue display panel 31 shown by the dotted line. The panel (33) is similarly placed at the position of the green display panel 33.

Furthermore, even if the order of arrangement of the dichroic mirrors that separate the three colors is different from the order of the embodiment, a similar composite display image can be obtained.

FIG. 5 is a spectral curve of a dichroic mirror.

In the figure, 50 is the blue spectral curve, 25 and 2B
This indicates that the blue reflecting mirror reflects light with a wavelength of approximately 500 (8M) or less, and transmits almost all other light. Similarly, according to the red spectral curve 51, the red reflecting mirrors 26 and 29 reflect light with a wavelength of 600 (syx) or more, and according to the green spectral curve 52, the red reflective mirrors 27 and 3
0 green reflective mirror has a wavelength of 500 (% chicken) to 600
It means that the light of (% chicken) is reflected.

FIG. 6 shows an equivalent circuit of a liquid crystal panel. In the present invention, a single active device that integrates thin film transistors in a liquid crystal panel! It uses a panel made by Trix.

In the figure, 60 is a gate line, which is connected to the gate of the thin film transistor 63, and is connected to the row 60 for displaying.
-1, 60-2...60-N and so on.

Reference numeral 61 denotes a source line, which is connected to an analog image signal, and is connected to 61-1 and 61-1 for temporally changing image signals.
61-2...61-N are written in sequence.

When a certain gate line 60 is selected, the N of that line
All the membrane transistors 65 become conductive, and charges corresponding to the image signal of the source line are accumulated in the capacitor formed by 64 pixel electrodes and 62 common electrodes. When the gate line 60 is not selected, the thin film transistor 63 becomes non-conductive, and the charge accumulated in the pixel electrode 64 is held until the gate line 60 is selected next.
A stable display can be obtained. In addition, since it can be displayed in analog quantities, smooth gradation can be displayed.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to realize a small and lightweight projection type display device because it is composed of a plate-like component consisting of a liquid crystal panel and a dichroic mirror, and the display images from three liquid crystal panels can be displayed inside the device. Since the images are combined using a dichroic mirror and projected using a single projection lens, it is possible to obtain a clear screen with no color shift up to the periphery of the screen.

In addition, since LCD panels with integrated thin film transistors can display images without using analog technology, they can display smooth gradations, and the composite image on the screen can be displayed in full color for each pixel, so even when enlarged, individual It is possible to obtain sharp images with inconspicuous pixels.

Since the pixel configuration of the liquid crystal panel can be freely changed depending on the purpose of use, it is possible to handle from small capacity display to large capacity display.

Furthermore, since colors are separated and images are combined using dichroic mirrors, each color is separated twice by the reflection of the dichroic mirror, making it possible to obtain a display image with good color purity. has.

[Brief explanation of drawings]

FIG. 1 is an external view of a projection display device. FIG. 2 is a top view showing the internal mechanism. FIG. 5 is a side view showing the internal mechanism. Figure 4 is a diagram of the principle of spectroscopy and synthesis using a dichroic mirror. Figure 5 is a spectral curve diagram of a dichroic mirror. Figure 6 is an equivalent circuit diagram of a liquid crystal panel. Inside-1? Maki-Nimachi Map No. 2! 1 ν] Clothes? Sensugaran 1 1. 4 members 6q Figure 3 %'□1 Bowl

Claims (1)

[Claims] A projection display device using a liquid crystal panel integrated with thin film transistors has three dichroic mirrors that separate visible light emitted from a light source into three primary colors, three dichroic mirrors that combine the three primary colors, and a display that corresponds to each of the three primary colors. A projection type display device characterized by being configured with three liquid crystal panels.